Thunderstorms & Hail

All thunderstorms are dangerous and every thunderstorm produces lightning. The Southeastern United States are very likely to have lightening and thunderstorms, especially in the summertime.

Development

Thunderstorms are the result of convection in the atmosphere. They are typically the by-product of atmospheric instability, where air masses of varying temperatures meet. Rapidly rising warm moist air serves as the engine for thunderstorms.

Characteristics

A typical thunderstorm may be three miles wide at its base, rise to between 40,000 to 60,000 feet in the troposphere, and contain half a million tons of condensed water. Conglomerations of thunderstorms along cold fronts (with squall lines) can extend for hundreds of miles.

Thunderstorms contain tremendous amounts of energy derived from water condensation. According to the National Weather Service, thunder storm is classified as severe when it produces one of three elements:

A tornado

Hail at least 0.75 inches in diameter

Winds at least 58 miles per hour

Occurrence

While thunderstorms can occur in all regions of the United States, they are most common in the central and southern states because atmospheric conditions in these regions are most favorable for generating powerful storms.

Hail

Hailstorms are a potentially damaging formation of severe thunderstorms. Hail is created when strong rising currents of air within the storm, called updrafts, carry water droplets to a height where they freeze.

Ice particles will continue to grow in size, eventually larger than .75 inches causing them to become too heavy to be supported by the updraft and fall to the ground.

Hail is larger than sleet and will only form inside a thunderstorm. The size of the hail stones are a direct function of the size and severity of the storm.

If in a forest: Seek shelter in a low area under a thick growth of small trees.

If in an open area: Go to a low place such as a ravine or valley. Be alert for flash floods.

On open water: Get to land and find shelter immediately.

Anywhere you feel your hair stand on end: Squat low to the ground on the balls of your feet. Place your ears over your head between your knees. Make yourself the smallest target possible and lessen your contact on the ground. DO NOT LIE FLAT on the ground.

Know the Terms

Familiarize yourself with these terms to help identify a thunderstorm hazard:

Severe Thunderstorm Watch - Tells you when and where severe thunderstorms are likely to occur. Watch the sky and stay tuned to NOAA Weather Radio, commercial radio or television for information.

Severe Thunderstorm Warning - Issued when severe weather has been reported by spotters or indicated by radar. Warnings indicate imminent danger to life and property to those in the path of the storm.

If you are driving, try to safely exit the roadway and park. Stay in the vehicle and turn on the emergency flashers until the heavy rain ends. Try not to touch metal or other surfaces that conduct electricity in and outside the vehicle.

Pulse - if the victim has a pulse and is breathing, look for other possible injuries. Check for burns where the lightning came into and left the body. Be alert for nervous system damage, broken bones and loss of hearing and eyesight.

After the storm passes think to:

Never drive through a flooded roadway. Turn around, don’t drown!

Stay away from storm-damaged areas to keep from putting yourself at risk from the effects of bad thunderstorms.

Keep listening to a NOAA Weather Radio or local radio and television stations for news and orders, as right to use roads or some parts of the area(s) may be blocked.

Help people who may need special assistance, such as infants, children and the elderly or those with access or functional needs.

Stay away from downed power lines. Report these lines quickly to the power company.

Watch your animals closely. Keep them under your direct control.

Additional Resources

Want to learn more about thunderstorms, lightning and hail? Visit these sites to learn about the science behind these systems and how to be prepared: